Guideline for the widget "Number Wheel"

Purpose of the Widget

The Number Wheel is used for easy adjustment of numeric values within a defined, small range (between 6 and 100 numbers). It is not useful for entering numbers within a large range or a decimal number with unknown decimals. An example is adjusting a time setting, since each part of the time is within a limited range. Another example would be if your application involves selecting an amount of money, but the selectable amounts of money are limited (e.g. up to 99.99). In that case you can use one wheel for the integer part and one for the decimal part. For ranges between 2 and 5 numbers (e.g. 1-5), the Number Stepper is preferred because it takes much less vertical space.

Description of the Widget

Each number wheel consists of three vertically aligned numbers: The selected number, the next number above and the previous number below. Multiple wheels may be stacked horizontally if a value consists of multiple blocks (e.g. time consisting of hours, minutes and seconds or currency consisting of dollars and cents). The user can adjust the number by "turning" the wheel. Sliding downward increases the number, sliding upward decreases it. If the movement stops between two numbers, the closer one snaps into place. The change applíes as soon the finger is lifted.

Number wheel.png

Code to Implement the Widget

TODO: Insert code

This page was last edited on 29 June 2012, at 21:40. Content is available under Creative Commons License SA 4.0 unless otherwise noted.